Noise filter on iPod dock

I recently completed a project where i made my own iPod Touch charging dock for a set of PC speakers. While testing it out i noticed there is some background noise/feedback coming through the speakers any time the iTouch is actually charging. Is there any way i can shield against this interference? Or is the proximity of the headphone jack to the iPod connecter to much of a problem to overcome without alterations to the iTouch itself? I've notice this problem before while listening to my iTouch through it's speaker or headphones when it was plugged into a wall charger or PC.

https://www.instructables.com/id/Laptop-Speaker-system-with-iPod-Touch-dock/